Reduction of Transmission Error Propagation in Adaptively Predicted, DPCM Encoded Pictures

This paper presents a new and simple technique to reduce error propagation in DPCM image coders that employ adaptive switchingtype prediction. An analytical performance description of this technique has not been obtained. However, simulation results using the Graham 1 adaptation algorithm are presented that demonstrate that-- in this case, at least--the technique can provide substantial reduction in channel error propagation without decreasing the transmission rate. The class of coders considered is those which adaptively choose one of Q fixed predictors Fq, q = 1, 2, · · Q, according to a decision rule that operates on the previously reconstructed pixels in the local past vicinity of the element to be predicted. If j i s the ith pixel on the yth line of the input raster, and is the vector of reconstructed pixels in the local past vicinity of (i,j), then the adaptive predictor has the form Xij = F(ytj), where F(-) is one of Q fixed functions Fq(-), q = 1, chosen according to a decision rule operating on yij, 1413